Lock nut for electrical conduits



Och 30, 1 928.

} J. A. MALCOLM LOCK-NUT FOR ELECTRICAL coNDuITs Filed Dec. 2?, 1925 A Quota,

Patented Oct. 30, 1928.

1,689,248 PATENT" OFFICE.

JOHN A. MALCOLM, OF CLEVELAND, OHIO.

LOCK NUT FOR ELECTRICAL CONDUI'IS.

Application filed December 27, 1923. Serial No. 682,990.

This invention relates to lock-nuts for electrical conduits, and has for its principal object to provide means for temporarily holding the ends of electric wire conduits in the outletboxes in order that concrete may be poured around said conduits and box withoutcausing the moving of same out of their set positions.

Another object of the invention is to provide a device of the above'character of simple,

inexpensive, and practical construction, which is convenient for use.

With the above and other objects in view, the invention will be hereinafter fully described as illustrated in the accompanying drawings, and the novel features thereof will be distinctly pointed out in the appended claims.

In the drawings similar characters of reference are used to designate corresponding parts.

Figure 1 is a View in sectional elevation illustrating a lock-nut constructed in accordance with my invention applied to an electrical conduit for holding same in an outlet-box.

Fig. 2 is a plan view of the outlet-box and lock-nut, the conduit being shown in section,

Fig. 3 is a similar view to Fig. 1, the nail for holding the lock-nut having been broken off and the lower or ordinary lock-nut having been applied to the conduit,

Fig. 4 is a perspective View of the lock-nut constructed in accordance with my invention, and

Fig. 5 is a similar view to Fig. 1 illustrating a modification of the invention.

Referring to the drawings, 1 represents an outlet-box or ceiling pan constructed of sheet material, the bottom 2 of which is provided with a plurality of openings as at 3 for receiving the downwardly turned end 4 of a pipe or conduit 5 for receiving electric wires. The end 4 of the conduit 5 passing through the bottom of said outlet-box is threaded at 6, and said outlet-box and conduit are of the usual construction as employed in the building of concrete floors for the installation of electric wires. The outlet-box 1 is adapted to be temporarily supported upon a board or con crete form 7, which is supported by uprights as 8, and the downwardly turned end 4 of the conduit 5 depends within said outlet-boX, and when in said positions are ready for the pouring of the concrete thereover. In order to hold the downwardly turned end 4: of the conduit 5 downwardly in position so that same will remain projecting the proper distance within the box after the concrete has been poured, a lock-nut 9 is provided. This locknut is in the form of a plate and is provided with a threaded opening near one end as 10 corresponding with the thread 6 of the downwardly turned end 1 of the conduit 5 for receiving same. Said lock-nut has an extension 11, which is provided with an aperture 12 for receiving a nail or other suitable fastening deice such as 13. Said nail passes through one of the openings 14 through the bottom 2 of the outlet-box 1 and is driven into the board 7 preferably at an angle for holding the locknut downwardly against the bottom of the outlet-box until the concrete is poured and has set. After the concrete has set sufficiently, the uprights 8 and board or concrete form 7 are removed, and said outlet-box and conduit are left in position. The nail 13 may be cut oil, and an ordinary lock-nut 15 is screwed onto the downwardly turned end 1 of the con duit 5 and tightened against the inner Sideof the bottom 2 of the outlet-box. Thus the conduit will be locked securely to the outlet-box by means of the lock-nuts 9 and 15.

In the modification illustrated in Fig. 5, instead of making the lock-nut 9 of suflicient thickness to receive threads, a thin plate 16 having a nail aperture 17 is provided to be used in the same manner in connection with an ordinary lock-nut 18 which is threaded onto the downwardly turned end 19 of the conduit. i

It is thought that the construction and a plication of this lock-nut will be clearly understood and its merits appreciated without further explanation, and it will be understood that slight changes in the details of construction and method of use may be made within the scope of the claims.

Having fully described my invention, what I claim is:

1. The combination of a concrete form, an outlet-box having its open end against the inner surface of said concrete form, said outlet-box having an opening through its bottom for receiving the conduit, a member resting upon the outer face of the bottom of said outlet-box adapted to hold the conduit in said opening of the outlet-box to prevent move ment of the conduit, the outlet-box having an aperture in its bottom, the member having an aperture adapted to register with the aperture in the bottom of the outlet-box, and a fastening means adapted to pass through said apertures and be secured to said con? crete form.

2. The combination of a concrete form, an outlet-box having its open end against the inner surface of said concrete form, said outlet-box having an opening through its bottom for receiving the conduit, a member resting upon the outer face of the bottom of said outlet-box adapted to hold the conduit in said opening of the outlet-box to prevent movement thereof downwardly, the outlet-box having an aperture in its bottom, the member having an aperture adapted to register With the aperture in the bottom of the out1et-b0x, and a fastening means adapted to pass through said apertures and be secured to said concrete form for preventing upward movement of said member.

8. The combination of a concrete form, an outlet-box having its open end against the inner surface of said concrete form, said outlet-box having an opening through its bottom for receiving a conduit, a member having a threaded opening therethrough for receiving the conduit, the member resting upon the outer face of the bottom of said outletbox adapted to hold the conduit in said opening of the outlet-box to prevent downward movement thereof, the outlet-box having an aperture in its bottom, said member having an aperture adapted to register with the aperture in the bottom of the outlet-box, and a fastening means adapted to pass through said apertures and be secured to said concrete form for holding said member in position.

In testimony whereof I atiix my signature.

JOHN A. MALCOLM. 

